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2 years ago

Can someone help me on this? Quite lost

Mathematics

1 answer:

zloy xaker [14]2 years ago

6 0

answer:

2. 3/2

1. y=-7

Step-by-step explanation:

You might be interested in

Use Cramer's Rule to solve the following system: –2x – 6y = –26 5x + 2y = 13

andriy [413]

$\bf \begin{cases}
-2x-6y&=-26\\
\quad 5x+2y&=13
\end{cases}\stackrel{\textit{determinant of the coefficients}}{D=
\begin{bmatrix}
-2&-6\\5&2
\end{bmatrix}}\implies (-4)-(-30)
\\\\\\
D=-4+30\implies \boxed{D=26}\\\\
-------------------------------\\\\$

$\bf x=\cfrac{D_x}{D}\implies x=\cfrac{
\begin{bmatrix}
\boxed{-26}&-6\\\\ \boxed{13}&2
\end{bmatrix}}{D}\implies x=\cfrac{(-52)-(-78)}{26}
\\\\\\
x=\cfrac{-52+78}{26}\implies x=\cfrac{26}{26}\implies \boxed{x=1}\\\\
-------------------------------\\\\
y=\cfrac{D_y}{D}\implies y=\cfrac{
\begin{bmatrix}
-2&\boxed{-26}\\\\ 5&\boxed{13}
\end{bmatrix}}{D}\implies y=\cfrac{(-26)-(-130)}{26}
\\\\\\
y=\cfrac{-26+130}{26}\implies y=\cfrac{104}{26}\implies \boxed{y=4}$

4 0

3 years ago

If f(x) = 3x - 9 and g(x) = x², what is (gºf)(5)?

Xelga [282]

Answer:

Step-by-step explanation:

Here, f(x) is the input to g(x), forming a composite function.

To evaluate (gºf)(5),

1) find the value of f(5). It is f(5) = 6.

2) Use this result as the input to g(x): g(6) = (6)^2 = 36

3 0

3 years ago

Find AB. Please please hurry

Anarel [89]

Answer:

i pick my answer as 3

Step-by-step explanation:

7-4=3

6 0

3 years ago

Read 2 more answers

To earn an A in an algebra course, a student must have a test average of at least 90. Mary has grades of 95, 82, 88 on her first

Fofino [41]

Answer: Mary need to make at-least 95 on her fourth test to earn an A in her algebra course.

Step-by-step explanation:

Let x be the grades scored by Mary in the fourth algebra test.

Mary has grades of 95, 82, 88 on her first three algebra tests.

Then, the combined scores in four test will become = 95+82+88+x = 265+x

Average score = (Sum of all scores) ÷ (Number of tests)

$=\dfrac{265+x}{4}$

As per given ,

To earn an A in an algebra course, a student must have a test average of at least 90.

i.e. Average score ≥ 90

$\Rightarrow\ \dfrac{265+x}{4}\geq90\\\\\Rightarrow\ 265+x\geq 90\times4=360\\\\\Rightarrow\ x\geq360-265 =95\\\\\Rightarrow\ x\geq90$

Hence, Mary need to make at-least 95 on her fourth test to earn an A in her algebra course.

5 0

2 years ago

A basketball is shaped like a sphere as shown in the diagram. The basketball has a radius of 4.7 inches.

netineya [11]

Answer:

V≈434.89

Step-by-step explanation:

V=4/3πr^3

plug the numbers in and you get 434.89

8 0

2 years ago